One book recommended by AlexMartelli and others present: [http://www.apress.com/book/bookDisplay.html?bID=93 Practical Python], by Magnus Lei Hetland
There's an education SIG, complete with mailing list: [http://python.org/sigs/edu-sig/ EduSig]
Also useful is the free writing at [http://ibiblio.org/obp/pyBiblio pyBiblio] (part of iBiblio, formerly SunSite).
We could really use some success stories of Python in education.